Source : Webster's Revised Unabridged Dictionary (1913)

Slaughterous \Slaugh"ter*ous\, a.
   Destructive; murderous. --Shak. --M. Arnold. --
   {Slaugh"ter*ous*ly}, adv.

Source : WordNet®

slaughterous
     adj : accompanied by bloodshed; "this bitter and sanguinary war"
           [syn: {gory}, {sanguinary}, {sanguineous}, {butcherly}]